Israel\'s negotiating position with the Palestinians in US-sponsored peace talks is the toughest it has taken since before the 1993 Oslo Accords, a senior Palestinian official said on Tuesday. \"The current Israeli negotiating position is the worst in more than 20 years,\" said Yasser Abed Rabbo, a top official with the Palestine Liberation Organisation, adding there had been \"no tangible progress\" in talks that resumed in July.